Truck hoist cradle

ABSTRACT

A pair of end members are hinged to wheel well and plates and hinged ramps extend across the ends of the wheel well members. Chains or cables extend between said members and the ramps to raise the end members vertically and the ramps upwardly at an angle to the floor when the hoist is raised. The chains permit the end members and the ramp to lie flat on the floor when the hoist is in the lowermost position.

United States Patent [1 1 Rowan et al. 1 Jan. 2, 1973 541 TRUCK HOISTCRADLE 2,593,664 4/1952 Fearfield'et al "2 94/67 E [76] Inventors:Donald James Rowan; Kenneth Lorne Rowan, both of PO. Box 91; PrimaryExaminer-hon Blunk Larry James Rowan, P.O. Box 54, AssistantExaminer-Douglas C. Bellis all of Elkhorn Manitoba, Canada Att rney-C.C- Kent et al'.

[22] Filed: I Aug. 16, 1971 [57] ABSTRACT I .2 72, [2 1 Appl No 1 155 Apair of end members are hinged to wheel well and plates and hinged rampsextend across the ends of the UnS- E, whee] wen membe s Chains o cablesextend between [51] Int. Cl ..B66c 1/ 12 i members and the ramps toraise the end members [58] Field Of Search 294/6715, 82 AH verticallyand the ramps upwardly at an angle to the floor when the hoist israised. The chains permit the [56] References cued end members and theramp to lie flat on the floor UNITED STATES PATENTS when the hoist is inthe lowermost position; 2,818,296 12/1957 Brennan et al ..294/67 E 10Claims, 10 Drawing Fi ures PATENTED 2W5 3.708.197

SHEET 1 OF 2 FIG.4-

miminm awn 3.708.191

SHEET 2 BF 2 INVENTOR TRUCK IIOIST CRADLE This invention relates to newand useful improvements in truck hoist cradles, particularly truck hoistcradles used at grain elevators whereupon it is conventional for a truckto drive onto a cradle by the front wheels thereof and the cradle ishoisted upwardly thus allowing the truck to dump the grain or othercontents rapidly and easily.

Conventional hoist cradles suffer from several disadvantages, theprincipal one of which is the fact that often the truck rolls from thecradle during the hoisting operation with considerable damage ensuingboth to the truck and to the cradle.

Another disadvantage of conventional hoist cradles is the fact that thepoint of hoist is often below axle of the wheels so that the center ofroll is above the hoist attachment thus causing, under some conditions,the cable to swing under and away from the wheels as the joistingoperation takes place once again permitting the truck to becomedisengaged from the hoist.

A further disadvantage of conventional hoist cradles is the slowness ofwhich they may be readied for receiving the truck and the slowness withwhich they lower the ramps to permit the truck to drive away. It shouldbe understood that in busy seasons, quick turn around is essential notonly to the elevator operator but also to the trucker who may have manytrips to make with loads of grain, feed and the like.

The present invention overcomes all of these disadvantages by providinga truck hoist which rapidly raises the ramps and lowers same, which hasa point of hoist above the rolling center of the axle, and which isextremely safe in use due to the relationship between the various parts.

The principal object and essence of the invention is therefore toprovide a truck hoist cradle of the character herewithin described inwhich the ramps are raised prior to the lifting operation beinginitiated and which furthermore permits the ramps to be lowered as soonas the hoist engages the supporting surface or ground during thedownward movement.

A further object of the invention is to provide a deviceof the characterherewithin described in which the lifting load is taken by endcomponents rather than by'linkage which raises and lowers the ramps.

Still another object of theinvention is to provide a device of thecharacter herewithin described in which the lifting load is taken by endcomponents rather than by linkage which raises and lowers the ramps.

Still another'object of the invention is to provide a device of thecharacter herewithin described in which the point of hoist is above therolling center of the axle.

Another object of the invention is to provide a device of the characterherewithin described which is simple in construction, economical inmanufacture, and otherwise well suited to the purpose for which it isdesigned.

With the foregoing in view, and such other or further purposes,advantages or novel features as may becomeapparent from consideration ofthis disclosure and specification, the present invention consists of,and is hereby claimed to reside in, the inventive concept which iscomprised, embodied, embraced, or included in the method, process,construction, composition, arrangement or combination of parts, or newuse of any of the foregoing, of which concept, one or more specificembodiments of same are herein exemplified plates.

. 2 as illustrative only of such concept, reference being had to theaccompanying Figures in which:

FIG. 1 is an end view of the cradle in the ground engaging position.

FIG. 2 is an end view of the cradle in the hoisting position.

FIG. 3 is a side elevation of one of the nd components.

FIG. 4 is a front elevation of one of the main attaching plates. 7

FIG. 5 is a top plan view of the cradle in the lowermost position.

I FIG. 6 is a front elevation of the cradle in the hoisting position.

FIG. 7 is a top plan view of the cradle showing an al ternativeembodiment.

FIG. 8 is an end view of FIG. 7.

FIG. 9 is a fragmentary front elevation of the preferred embodiment ofthe upper part of the hoist FIG. 10 is a view similar to FIG. 9 but withthe pulley adaption component secured thereto. g

In the drawings like characters of reference indicate correspondingparts in the different figures.

Proceeding therefore to describe the invention in detail, I haveprovided a plurality of cross members 10 and 11 situated in spaced andparallel relationship, the members 10 being classified as the outermostmembers, and the members 11, the inner members.

A front ramp 12 extends across the front ends of the cross members 10and 11 and is hingedly secured thereto by means of hinge pins 13 passingthrough hinge components 14. g

A rear ramp 15 extends a cross the rear ends of the cross members 10 and11 and is hingedly secured thereto in a similar manner, by means ofhinge pins 13 and hinge members 14.

A cutout portion 16 is formed within the rearrnost edge 16 of the rampl5 so that when it is in the raised position,.it clears the exhaust pipeof the truck engaged within the hoist.

End components collectively designated 18 are provided and take the formof a substantially truncated triangular main attaching plate 19 having avertical slot 20 formed .therethrough and centrally located as clearlyshown in FIG. 4. I-Iinge components 21 are provided upon the lower edge22 of the plate 19 and corresponding components 21 are provided upon theouter edges of the outermost cross members 10.

Hinge pins 23 connect the main attaching plates to tllre outermost crossmembers 10 inhinging relations 1p. 1

A pair of hoist plates 24 are situated in spaced and parallelrelationship and are joined together by means of a bar or strip 25welded to the inner surfaces of the two plates 24 as clearly shown inFIG. 3.

It should be appreciated that the bar or means 25 engages slot 20 sothat the two plates have to be assembled in conjunction with the mainattaching plate 19 and then welded into position thus permitting thehoist plates to move vertically due to the engagement of the bar 25,within the limits of slot 20 and it is desired that the slot 20 beapproximately twice as long as the bar or means 25. i

A pulley assembly taking the form of a V-pulley 26 is journalled uponpin 27 within a carrier 28 which in turn is hinged to the upper ends ofthe hoist plates 24 and cable 29 extends to a conventional hoistsituated above the cradle, said hoist notbeing illustrated.

Linkage taking the form of chains 30 or flexible cables, extends betweenthe ends of the ramps 12 and 15 and the upper end of the hoist plates 24as shown in FIGS. 1, 2 and 5.

In operation, and assuming the cradle is in the position shown in FIG.5, it will be noted that the ramps 12 I are flat upon the ground orsupporting surface and the end components 18 have also folded outwardlyto lie flat upon the supporting surface. This permits unrestrictedaccess to the cradle by the truck being unloaded which drives upon thecradle so that the front wheels'engage the wheel well areas 31 definedby the pairs of cross members and 11 and the portions of the front andrear ramps 12 and extending across the ends of these cross members.

Reference character 32 shows in phantom the outline of a wheel of atruck in position and it will be-observed that the center of this wheelwhich coincides v with the axle thereof is well below the hoisting orlifting axis which is defined by the pin 27 upon which pulley 2.6 ismounted.

The hoist is then operated to raise the cradle and the initial actionlifts or raises the hoist plates 24 upwardly with respect to the mainplate 19 until the upper end of therod 25 engages the upper end of slot20. In this position, the chains 30 have been raised also thus liftingthe ramps upwardly at an angle around their hinge pins, to a positionshown in FIG. 2 whereupon they engage the tires of the vehicle upon thecradle.

Further lifting raises the entire cradle together with the front of thetruck thereon and it should be observed thatthis load is carried not bythe chains 30 but by the engagement of the rod or bar 25 within theupper end of slots 20. I

After thetruck has been unloaded in the usual way, the hoist is loweredand as-soon as the cradle engages the supporting surface or groundrepresented by reference character 33, the hoist plates move downwardlywith relation to slots thus permitting the ramps to flatten and lie uponthe ground or supporting surface. This permits the truck to be drivenfrom the ramp immediately and further lowering of the hoist will permittheend components 18 to move outwardly to take up the flat positionshown in FIG. 5 so that the cradle is ready for the next truck to bedriven thereon.

FIGS. 7 and 8 show an alternative embodiment of the construction inwhich the principal is similar.

' Front ramp l2 and rear ramp 15 are connected together by lengths ofchain 34 extending between the inner edges 35 of the ramps in spaced andparallel relationship as clearly shown in FIG. 7. v

The main attaching plates 19 are similar in configuration to thosehereinbefore described but the hoist plates are eliminated. The pulley26 is attached to the upper ends 36 of these main attaching plates in asimilar manner although this has not been illustrated in FIGS. 7 and 8.

End hinge pins 37 engage the hinge portions 21A of the main attachingplates adjacent the lower edges 22 thereof and these hinge pins areangulated at the ends thereof to engage hinge portions 38 formed on theouter comers of the ramps 12 and 15 as clearly shown.

It will therefore be appreciated that the main attaching plates 19 maylie flat upon the ground as shown in FIG. 7 when in the lowermostposition yet may be moved to the vertical position by means of theconventional hoist as hereinbefore described. As the cradle is liftedfrom the ground, the weight of the ramps .12 and 15 cause the inneredges 35 to move downwardly until restrained by chains 34 and as shownin FIG. 8. The wheels of the truck will test between adjacent pairs oflengths of chain 34 so that the cradle effect is maintained, it beingunderstood, of course, that the point of hoist is above the axle of thefront wheels.

FIGS. 9 and 10 show the preferred construction of the hoist plates 24 inwhich the bar or strut 25 is extended above the plates 24 in the form ofan apertured extension 25A. The overhead hoist (not illustrated) may beengaged directly in aperture 258 or alternatively, the pulley assemblymay be attached to this extension.

The carrier 28 includes a pair of attaching straps 39 secured to crosspin 40 which in turn engages bearing sleeve 41 formed on the upper sideof an adaptor component 42. i

This adaptor component is in turn bolted to extension 25A by means ofnut and bolt assembly 43 passing through aperture 258.

The chains 30 are secured by bolts 44 engaging through apertured collars45 welded to each side of plates 24. A nut 46 engages the bolt withinthe collar thus permitting limited length adjustment of the chain. Thisadjustment is desirable to suit conditions and to enable the operator toadjust the inclination of the ramps as he may wish, within limits. I

What is claimed to be the present invention is:

l. A truck hoist cradle comprising in combination a pair of transverselyextending ramps, a plurality of spaced apart cross members, said rampsbeing hingedly secured to the ends of said cross members, said ramps andsaid cross members defining a pair of wheel receiving wells, endcomponents secured to the-outermost of said cross members, and linkagemeans extending between said ramps and said end components andcooperating to raisesaid' ramps when said cradle is hoisted and to lowersaid ramps when said cradle is in the lowermost position upon asupporting surface.

2. The cradle according to claim 1 in which the connection between saidend components andsaid outermost cross members is hinged whereby saidend components also'lie flat when said hoist cradle is in the lowermostposition upon a supporting surface.

3. The hoist cradle according to claim 1 in which said end componentscomprise a main attaching plate, and a hoist plate slideable withinlimits, with respect to said main attaching plate, whereby said rampsare raised by said linkage prior to said cradle being hoisted and/orlowered by said linkage as soon as said cradle engages the supportingsurface. I

4 The hoist cradle according to claim 2 in which said end componentscomprise a main attaching plate, and a hoist plate slideable withinlimits, with respect to said main attaching plate, whereby said rampsare raised by said linkage prior to said cradle being hoisted and/orlowered by said'linkage as soon as said cradle engages the supportingsurfaces.

5. The hoist cradle according to claim 1 in which said end componentsinclude a main attaching plate, a vertical slot formed therein, a pairof hoist plates one upon each side of said main plate, and meansextending between said hoist plates and engageable within said slot,said slot being approximately twice as long as said means.

6. The hoist cradle according to claim 2 in which said end componentsinclude a main attaching plate, a vertical slot formed therein, a pairof hoist plates one upon each side of said main plate, and meansextending between said hoist plates and engageable within said slot,said slot being approximately twice as long as said means.

7. The hoist cradle according to claim 1 in which said linkage comprisesa length of flexible material, and a pulley assembly detachablysecurable to said hoist plates at the upper ends thereof and means todetachably secure said pulley assembly to said hoist plates in pivotalrelationship thereto.

8. The hoist cradle according to claim 2 in which said linkage comprisesa length of flexible material, and a pulley assembly detachablysecurable to said hoist plates at the upper ends thereof and means todetachably secure said pulley assembly to said hoist plates in pivotalrelationship thereto.

9. The hoist cradle according to claim 3 in which said linkage comprisesa length of flexible material, and a pulley assembly detachablysecurable to said hoist. plates at the upper ends thereof and means todetachably secure said pulley assembly to said hoist plates in pivotalrelationship thereto.

10. The hoist cradle according to claim 4 in which said linkagecomprises a length of flexible material, and a pulley assemblydetachably securable to said hoist plates at the upper ends thereof andmeans to detachably secure said; pulley assembly to said hoist plates inpivotal relationship thereto.

1. A truck hoist cradle comprising in combination a pair of transverselyextending ramps, a plurality of spaced apart cross members, said rampsbeing hingedly secured to the ends of said cross members, said ramps andsaid cross members defining a pair of wheel receiving wells, endcomponents secured to the outermost of said cross members, and linkagemeans extending between said ramps and said end components andcooperating to raise said ramps when said cradle is hoisted and to lowersaid ramps when said cradle is in the lowermost position upon asupporting surface.
 2. The cradle according to claim 1 in which theconnection between said end components and said outermost cross membersis hinged whereby said end components also lie flat when said hoistcradle is in the lowermost position upon a supporting surface.
 3. Thehoist cradle according to claim 1 in which said end components comprisea main attaching plate, and a hoist plate slideable within limits, withrespect to said main attaching plate, whereby said ramps are raised bysaid linkage prior to said cradle being hoisted and/or lowered by saidlinkage as soon as said cradle engages the supporting surface.
 4. Thehoist cradle according to claim 2 in which said end components comprisea main attaching plate, and a hoist plate slideable within limits, withrespect to said main attaching plate, whereby said ramps are raised bysaid linkage prior to said cradle being hoisted and/or lowered by saidlinkage as soon as said cradle engages the supporting surfaces.
 5. Thehoist cradle according to claim 1 in which said end components include amain attaching plate, a vertical slot formed therein, a pair of hoistplates one upon each side of said main plate, and means extendingbetween said hoist plates and engageable within said slot, said slotbeing approximately twice as long as said means.
 6. The hoist cradleaccording to claim 2 in which said end components include a mainattaching plate, a vertical slot formed therein, a pair of hoist platesone upon each side of said main plate, and means extending between saidhoist plates and engageable within said slot, said slot beingapproximately twice as long as said means.
 7. The hoist cradle accordingto claim 1 in which said linkage comprises a length of flexiblematerial, and a pulley assembly detachably securable to said hoistplates at the upper ends thereof and means to detachably secure saidpulley assembly to said hoist plates in pivotal relationship thereto. 8.The hoist cradle according to claim 2 in which said linkage comprises alength of flexible material, and a pulley assembly detachably securableto said hoist plates at the upper ends thereof and means to detachablysecure said pulley assembly to said hoist plates in pivotal relationshipthereto.
 9. The hoist cradle according to claim 3 in which said linkagecomprises a length of flexible material, and a pulley assemblydetachably securable to said hoist plates at the upper ends thereof andmeans to detachably secure said pulley assembly to said hoist plates inpivotal relationship thereto.
 10. The hoist cradle according to claim 4in which said linkage comprises a length of flexible material, and apulley assembly detachably securable to said hoist plates at the upperends thereof and means to detachably secure said pulley assembly to saidhoist plates in pivotal relationship thereto.